Adding some types to the GIT world
git_tests: dispose of tmp dir when done
Git: tests for valid shas
tabs matter
bot_git: TreeEntry
bot_git: tweaks to error output
GitDir learned lsTree

using it in git hop_tasks
GitDir: getBranches -> getBranchNames
GitDir: learned getBranchReferences

used in hop_tasks git magic
bot_git: GitReference and BranchReference learned toString